<!DOCTYPE html>
<html lang="zh">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        div img {
            /* filter: blur()---图片模糊处理，括号数值越高，图片越模糊，注意数值要加单位 */
            filter: blur(5px);
        }
        div img:hover {
            /* 鼠标经过取消模糊 */
            filter: blur(0);
        }
    </style>
</head>
<body>
    <div><img src="images/img.jpg" alt=""></div>
</body>
</html>